Prevention of Drinking and Driving.

Since the early 1980's, legislative initiatives, such as the minimum legal drinking age of 21, administrative license revocation, and lower legal blood alcohol concentration limits for youth and adults, have significantly decreased alcohol-related traffic fatalities. General deterrence legislation is aimed at dissuading the general public from driving after drinking, whereas specific deterrence laws seek to prevent people who have been convicted for driving under the influence from repeating their offense. Education, enforcement, and comprehensive community programs, combined with legislation, can substantially reduce alcohol-related traffic deaths.

T raffic crashes are the leading drivers in singlevehicle fatal crashes are disproportionately involved in cause of death in the United with those of drivers stopped at ran alcoholrelated traffic deaths. Approx States for persons ages 1 to 34 dom in nationwide surveys indicates imately 3 in 5 Americans will be in (Insurance Institute for Highway Safety that each 0.02percent increase in BAC volved in an alcoholrelated crash at 1995). In 1995, 41 percent of fatal traf nearly doubles a driver's risk of being some point in their lives (NHTSA and fic crashes involved a driver or pedestri in a fatal crash (Zador 1991). The risk National Institute on Alcohol Abuse an who had been drinking (National increases more rapidly with each drink and Alcoholism [NIAAA] 1996). In Highway Traffic Safety Administration for drivers under age 21, who have less [NHTSA] 1996b). This article reviews experience in driving and who, as a addition, alcoholimpaired driving the nature and extent of the drinking group, more often take risks in traffic, often has an impact on innocent vic driving problem in the United States, such as speeding or failing to wear tims. In 1995, 39 percent of people discusses major legal and community seatbelts. For all groups of drivers, fatal killed in crashes involving drivers initiatives in the past 15 years to re crash involvement per miles driven who had been drinking were persons duce the problem, and examines other increases ninefold at BAC's of 0.05 other than the drinking driver. potential interventions for further re to 0.09 percent (Zador 1991 Alcoholrelated traffic crashes cost society $45 billion annually in hospi tal costs, rehabilitation expenses, and lost productivity (NHTSA 1995a). In 1995 more than 1.4 million people were arrested for driving while intoxicated, nearly 10 percent of all arrests made that year.

RECENT TRENDS IN ALCOHOL RELATED TRAFFIC DEATHS
The United States, like several other countries, has experienced marked declines in recent years in the number of fatal crashes involving alcohol. In 1982, when NHTSA began estimating the proportion of fatal crashes nation wide that involved alcohol, 25,165 fatal crashes (57.2 percent of all fatal crashes) involved a driver or pedestrian who had been drinking. In 1995 alcohol was involved in 17,274 crash fatalities, or 41.3 percent of all crash fatalities. Be tween 1982 and 1995, the proportion of crash fatalities involving alcohol fell by 28 percent, and the number of crash fatalities involving alcohol dropped by 31 percent (NHTSA 1996a).
Many improvements in traffic safety have occurred since 1982, such as the adoption of laws requiring the use of child restraints in all States and the enactment of legislation mandating the use of seatbelts in 49 States. However, the decline in alcoholrelated traffic deaths was independent of these laws: Traffic deaths that did not involve alco hol increased 28 percent from 18,780 in 1982 to 24,524 in 1995. The greatest declines in alcohol related traffic deaths were among youth under 21. Among people ages 15 to 20, alcoholrelated traffic deaths declined by 59 percent between 1982 and 1995, from 5,380 to 2,201. In this age group, the proportion of fatalities involving alcohol declined from 63 percent in 1982 to 36 percent in 1995, a 43percent decline. Despite the longterm decline since 1982 in alcoholrelated traffic deaths, a 4percent increase in such deaths (from 16,589 to 17,274) oc curred between 1994 and 1995, the first increase in 10 years. The in crease occurred among persons age 21 and over.

GRASS ROOTS ACTIVISM
A key social change behind efforts to reduce drunk driving was the estab lishment in the early 1980's of grass roots organizations such as Mothers Against Drunk Driving (MADD), Stu dents Against Drunk Driving (SADD), and Remove Intoxicated Drivers (RID). Along with its support for victims af fected by drunk drivers and its public education activities, MADD monitors research findings and, through leg islative compendia, workshops, and national report cards rating the States, presents findings from this research and other testimony to State legislators. According to NHTSA (1996a), since 1982 more than 2,000 State laws have been passed in an effort to reduce alcoholimpaired driving. MADD has been an important force behind many of those laws.

Methodological Problems
Several factors make it difficult for re searchers to isolate the effects of spe cific laws in reducing drunk driving. First, several laws are often passed in a given State within a relatively short time period, making it difficult to sepa rate fully the effects of each law. Sec ond, publicity about the drunkdriving problem is aired across State borders, diminishing any differences that may be found between States with differ ent legislation.
Third, because most States do not determine BAC's of all drivers in volved in fatal crashes, researchers often rely on surrogate (i.e., proxy) measures of alcohol involvement in fatal crashes, such as singlevehicle nighttime (SVN) fatal crashes. SVN fatal crashes are three times more likely than other fatal crashes to in volve alcohol. However, this proxy measure can be conservative: SVN fatal crashes account for less than one half of all fatal traffic crashes involv ing intoxicated drivers. Consequently, the use of surrogate measures intro duces some imprecision in evaluating the effects of legislation, particularly in shortterm studies involving small jurisdictions. Variability in outcome measures from study to study makes crossstudy comparisons difficult.
Fourth, people who drive after heavy drinking (defined as five or more drinks at one sitting) are much more likely to engage in other risky driving behaviors, such as speeding, running red lights, making illegal turns, driving after other drug use, and failing to wear seatbelts. Therefore, studies should control for shifts in legislation, targeting these behaviors (i.e., in creased enforcement of traffic laws) as well as measuring overall changes in these behaviors.
Despite these methodological con cerns, a number of conclusions can be reached concerning the effects of vari ous legislative interventions in reduc ing alcoholimpaired driving.

MAJOR LEGISLATIVE CHANGES TO REDUCE ALCOHOL IMPAIRED DRIVING
Legal efforts to reduce alcohol impaired driving have emphasized deterrence. Deterrence laws seek to prevent alcoholinvolved drivingthrough swift, certain, and severe penalties if warranted. Deterrence laws fall into two categories: (1) general deterrence laws, which aim to prevent the general public from ever driving after drinking, and (2) specific deter rence laws, which seek to prevent con victed DUI offenders from repeating their offense. Although convicted DUI offenders are at greater risk than other drivers for subsequent rearrest and crash involvement, most drivers in fatal crashes involving alcohol have never been previously convicted. In fact, twothirds of persons arrested for DUI have never been arrested before (NHTSA 1995a,b). This statistic un derscores the important need for laws and programs aimed at both general and specific deterrence.

MLDA of 21.
In all States it is currently illegal to sell alcohol to persons under age 21. Numerous research studies indicate that raising the minimum legal drinking age (MLDA) to 21 reduces alcoholrelated fatal crash involvement among youth. States adopting MLDA's of 21 in the early 1980's experienced a 10 to 15percent decline in alcohol related traffic deaths among drivers in the targeted ages, compared with States that did not adopt such laws. NHTSA (1995a) estimated that MLDA's of 21 have prevented more than 14,800 traffic deaths since 1976, approximately 700 to 1,000 deaths annually for the past decade. MLDA laws not only have re duced drinking among persons under age 21, they also have lowered drink ing among people ages 21 to 25 who grew up in States with MLDA's of 21 relative to those who grew up in other States (O'Malley and Wagenaar 1991).
Other nations that do not have an MLDA of 21 have experienced de clines in alcoholrelated fatalities among drivers under 21 (National Research Council of the Transporta tion Research Board 1994), as have many States that did not initially adopt an MLDA of 21. However, the evi dence is clear and rather consistent that U.S. States which raised the legal drinking age experienced greater de clines in fatal crashes likely to involve alcohol among drivers under 21 than did States that initially retained lower drinking ages (General Accounting Office 1987).

Criminal Per Se Laws. Every State except Massachusetts and South
Carolina has adopted laws that make it a criminal offense per se to drive with a BAC above the State's legal limit, which is generally either 0.10 or 0.08 percent. The per se provision means that prosecutors do not have to introduce evidence other than BAC to demonstrate impairment, making con victions easier to obtain.

Administrative License Suspension.
This law allows a police officer or other official to immediately confiscate the license of a driver whose BAC ex ceeds the legal limit. License actions thus occur closer to the time of infrac tion and, by bypassing the court, are more swift and certain. Although these laws have faced some challenges for allegedly imposing double jeopardy on a driver who subsequently is con victed of DUI and receives additional penalties, no State supreme court has upheld such a challenge. In 1988 the Insurance Institute for Highway Safety conducted a nationwide comparison of administrative revocation laws, crimi nal per se laws, mandatory jail laws, and community service laws passed between 1978 and 1985 (Zador et al. 1989). Administrative license revo cation laws were accompanied by a 5percent decline in fatal crashes, compared with a 2percent decline for other types of laws, such as criminal per se laws.

ZeroTolerance Laws. Thirtyseven
States and the District of Columbia now have adopted zerotolerance leg islation, laws that make it illegal for drivers under 21 to drive after drink ing any alcohol. Laws setting legal BAC limits of 0.00 to 0.02 percent are considered zerotolerance laws. A recent study compared the first 12 States that lowered legal BAC's for drivers under 21 with 12 nearby States that did not. States adopting zero tolerance laws experienced a 20percent greater decline in the proportion of SVN fatal crashes among 15 to 20 yearold drivers. States lowering BAC limits to 0.04 or 0.06 did not experi ence significant declines relative to comparison States in the proportion of SVN fatal crashes among this age group (Hingson et al. 1994). The study projected that if the remaining States adopted zerotolerance laws and ex perienced comparable declines, 375 to 400 fewer fatal cashes would occur each year. Zerotolerance laws may be effective because they convey a clear message to youth: Drivers under 21 may not drive after any alcohol con sumption whatsoever.
One problem encountered in im plementing these laws has been the difficulty in achieving broad aware ness of the law. Studies in California and Massachusetts found that 45 to 50 percent of young drivers were un aware of the law. Blomberg (1992), in a quasiexperimental study of an awareness campaign involving public service announcements about Mary land's zerotolerance law, found a onethird greater decline in alcohol involved crashes among drivers re ceiving intensive education than among drivers who received no in tensive education.

The 0.08Percent Per Se Laws for Drivers Over Age 21.
Thirteen States have adopted criminal per se laws lowering the legal BAC from 0.10 to 0.08 percent. Massachusetts has set the BAC for its administrative license revocation law at 0.08 percent. Johnson and Waitz (1995) moni tored six different measures of driver alcohol involvement in the first five States to adopt 0.08percent per se laws and identified several statistically sig nificant pre to postlaw decreases. However, comparison areas with dif ferent per se limits were not included; the study therefore could not determine whether postlaw declines were inde pendent of general regional trends.
A subsequent analysis (Hingson et al. 1996a) paired the first five States to adopt a 0.08percent legal BAC limit with five nearby States that retained the 0.10percent legal limit. As a group, States that adopted the 0.08percent limit experienced a statistically sig nificant 16percent postlaw decline in the proportion of fatal crashes in volving fatally injured drivers at 0.08 percent BAC and higher. They also experienced a statistically significant 18percent postlaw decline in the proportion of fatal crashes involving fatally injured drivers at 0.15percent BAC and higher. Four of the five 0.08 percent States experienced greater postlaw declines than did comparison States. In the three largest of the five 0.08percent States, the declines were significantly greater than in their re spective comparison States. Those three pairs of States accounted for more than 90 percent of the fatal crashes in the study. During the pre and postlaw period, more than 80 percent of fatally injured drivers were given blood alco hol tests in 0.08percent States.
Compared with 0.10percent States, the 0.08percent States may have been more concerned about alcoholimpaired driving and more responsive to legisla tive initiatives to reduce the problem. All five 0.08percent States had admin istrative license revocation laws during the study period, three of which were implemented within 1 year of the 0.08 percent law. Administrative license revocation laws have been associated with a 5percent decline in fatal crashes and as much as a 9percent decline in alcoholrelated fatal crashes (Klein 1989). This potential effect restricted the study's ability to separate the ef fect of 0.08percent laws from that of administrative license revocation laws. Only in Maine was administrative li cense revocation in place throughout the prelaw analysis period prior to adoption of the reduced BAC limit. Thus, Maine was the only State where it was possible to identify an indepen dent effect of the 0.08percent law.
The results of this study suggest that 0.08percent laws combined with administrative license revocation can reduce the proportion both of fatal crashes involving drivers and of fa tally injured drivers at 0.08percent BAC or higher and at 0.15percent BAC or higher. The study projected that if all States adopted 0.08percent laws-with results similar to those of the first five States to adopt such laws-at least 500 to 600 fewer deaths would occur on the Nation's roadways each year.
In 1994 Massachusetts simultane ously introduced a 0.08percent BAC and administrative license revocation laws. Statewide randomized telephone surveys in 1993 (i.e., before the 0.08 percent BAC law was implemented) and in 1996 (i.e., after the law was implemented) revealed clear shifts in public perceptions of how much drivers could drink and still drive safely and legally. The proportion of respondents who believed they could consume four or more drinks and drive safely de clined from 24 to 15 percent, and the proportion who felt they could drive legally after more than four drinks dropped from 18 to 9 percent. At the same time, the proportion of respon dents who believed drunk drivers would have their license suspended before a trial rose from 47 to 71 per cent. In addition, the proportion of drivers who reported driving in the past month after consuming four or more drinks declined from 9 to 4 percent (Massachusetts Governor's Highway Safety Bureau 1996).

Specific Deterrence Laws
Persons convicted of alcoholimpaired driving are more likely than other drivers to be subsequently arrested for driving while intoxicated and to be involved in alcoholrelated crashes (NHTSA and NIAAA 1996). Specific deterrence laws seek to reduce this re cidivism through license actions, treat ment or rehabilitation, jail sentences, dedicated detention, probation, actions against vehicles and vehicle tags, lower legal BAC's for offenders, or some combination of these measures.
License Actions. Mandatory license suspensions are more effective than discretionary suspension in reducing total crashes and violations. Their ef fectiveness is attributed to the fact that the laws generate a perceived certainty of punishment and reduce the influence of judicial discretion. Evidence also indicates that diversion to treatment with either a restricted or a limited li cense leads to higher accident and vio lation rates than full license suspension. Several studies also report that full license suspension reduces DUI re cidivism. Much of this benefit may result from reduced driving exposure. NHTSA and NIAAA (1996) pre pared A Guide to Sentencing DUI Of fenders and reported the following: • Suspension periods between 12 and 18 months appear to be opti mal for reducing DUI recidivism.
• Suspension periods of less than 3 months seem to be ineffective.
• Although more than 50 percent of persons with suspended licenses continue to drive, they seem to drive less frequently and more cautiously in order to avoid arrest.

Treatment or Rehabilitation. Wells
Parker and colleagues (1995) recently completed a metaanalysis of treatment efficacy for DUI offenders. Compared with standard sanctions (i.e., jail or fines) or no treatment, rehabilitation generated a 7 to 9percent reduction in the incidence of alcoholrelated driving recidivism and crashes when averaged across all types of offenders and rehabilitation. Alcoholrelated crashes and violations constitute only a minority of total crashes and viola tions. Actions to restrict license use (e.g., daytimeonly driving permits) combined with some kind of remedial treatment have been found to be more effective in preventing alcoholrelated traffic incidents than full suspension. The analysis by WellsParker and colleagues (1995) also indicated that treatments combining punishment strategies, education, and therapy with followup monitoring and aftercare were more effective for firsttime as well as repeat offenders than any single ap proach. For example, combining treat ment with licensing action was more effective than either tactic alone. Ac cording to this analysis, treatment alone never substitutes for sanctions or remedies, and remedies and sanc tions do not substitute for treatment. Finally, weekend intervention pro grams designed to evaluate alcohol and other drug abuse and create an individualized treatment plan for of fenders have been found to produce lower recidivism rates than jail, sus pended sentences, or fines. Jail Sentences. Although incarcera tion incapacitates drivers during the period of confinement, minimal evi dence exists on the postincarceration effect of jail. Nichols and Ross (re viewed in NHTSA and NIAAA 1996) examined the specific deterrent effects of jail sentences for firsttime and re peat DUI offenders in a review of more than 80 studies of legal deterrence. Eight studies reported no reductions in DUI recidivism as a result of jail sentences, and only one recent study provided reasonably convincing evi dence of a 3year reduction for first time repeat offenders who received mandatory 2day jail sentences in Tennessee. In one study, long periods of incarceration were actually associ ated with higher recidivism (Mann et al. 1991). Although jail sentences may have some shortterm general deterrent effects, as well as deterrent effects for firsttime offenders, mandatory jail sentences tend to affect court oper ations and the correctional process negatively by increasing the demand for jury trials and plea bargains and by crowding jails (NHTSA and NIAAA 1996).

Dedicated Detention.
Detention facili ties specifically for DUI offenders can offer both incapacitation and supervised rehabilitation services. One program of this type, in Prince Georges County, Maryland, has been found to reduce recidivism among both firsttime and repeat offenders (Harding et al. 1989).
Probation. The 1996 NHTSA-NIAAA review of sentencing options found that probation may slightly reduce re cidivism among drivers at low risk for being repeat offenders, but proba tion alone does not measurably reduce recidivism among those at high risk. Although the effects of intensive pro bation and home detention have not been evaluated, a 7year study of elec tronic monitoring found that recidivism rates were less than 3 percent for a group of DUI offenders who were electronically monitored during 203 months of their combined probation. However, recidivism increased when the monitoring ended.

Actions Against Vehicles and Tags.
Although license actions have been shown to reduce recidivism, many people with suspended licenses con tinue to drive.
Unlicensed drivers can be appre hended only when police have proba ble cause to stop their vehicle. Wash ington and Oregon have enacted leg islation that allows police to seize the vehicle registration of drivers caught driving after suspension, leaving the motorist with a temporary, 60day registration. A sticker on the vehicle gives the police probable cause to stop the vehicle to ask for proof of license. Researchers have reported evidence of the law's effectiveness in Oregon but not in Washington. Rodgers (1994)  deterrent effect while the courts admin istered the system. In contrast, when the program was managed administra tively, offenders who lost their plates had a lower rate of recidivism than those who did not. Another approach-ignition inter locks to prevent vehicle operation when a driver's breath alcohol exceeds a designated limit-has been found to reduce recidivism, but recidivism may rise after the device is removed.
The NHTSA-NIAAA (1996) sen tencing guide identified several other sentencing approaches that have not been systematically evaluated, includ ing financial sanctions, publication of offenders' names in newspapers, atten dance at victimimpact panels, victim restitution programs, and courtordered visits to emergency rooms.

Lower Legal Blood Alcohol Limits for Convicted DUI Offenders.
De spite the fact that persons convicted of DUI are more likely than other drivers to be subsequently arrested for DUI or to be involved in crashes, almost all States allow the same legal BAC for these drivers as for drivers who have never been convicted of DUI. One exception is Maine. In 1988 the State set the legal limit at 0.04 percent for drivers previously convicted for DUI, lower than the 0.08 percent limit for other drivers. In the 3 years following enactment of the law, nighttime fatal crashes involving drivers with prior convictions declined by 38 percent, whereas such crashes increased by 50 percent in neighboring New Hampshire and Vermont (Hingson 1995).

Enforcement of Impaired Driving
Laws. The extent to which drunk driving laws are enforced can influ ence their impact on impaired driving. Drunkdriving arrests increased dramat ically between 1978 and 1983, from 1.3 to 1.9 million, but arrests have dropped each year since then, to 1.4 million in 1994. Estimates indicate that only 1 arrest is made for every 300 to 1,000 drunkdriving trips (Voas and Lacey 1989). Respondents in a 1995 national survey of 4,000 randomly selected drivers believed that people who drink and drive are more likely to be in an accident than to be stopped by the po lice. Only 23 percent of the respon dents thought it very likely that people who drive after drinking will be stopped by the police, down from 26 percent in 1993 (NHTSA 1996a).
The most dramatic example of the potential deterrent impact of police enforcement of drunkdriving laws occurred in Australia in New South Wales and Victoria, where random breath testing was introduced on a massive scale. In a given year, as many as 1 driver in 3 was stopped by the police. There was an immediate 37 percent drop in alcoholrelated fatal crashes, compared with the previous 3 years, and a sustained 24percent decrease over the next 5 years (NHTSA and NIAAA 1996).
In the United States, police do not have the authority to administer breath tests to individual drivers who have been stopped unless there is probable cause to believe that the driver is under the influence of alcohol. Instead, police must use surveillance by police patrols or sobriety checkpoints, often at pre designated, highrisk areas and involv ing several patrol officers. Several evaluations of sobriety checkpoints have demonstrated their effectiveness. One recent California study found that checkpoints reduced alcohol related crashes regardless of the way in which they were implemented (e.g., using from 3 to 5 officers versus using from 8 to 12 officers) or whether the officers remained at one location for an entire evening or moved to multi ple locations.
Although checkpoints have consid erable deterrence potential, they are limited in that many drunk drivers pass through roadblocks undetected. Research involving checkpoints where drivers not detained by police were subsequently tested for alcohol indi cates that about onehalf of the drivers with BAC's above the legal limit are not detained (Ferguson et al. 1995).
Passive alcohol sensors increase detection of drunk drivers in sobriety checkpoints. Passive sensors collect air from in front of a driver's face and can detect the presence of alcohol in the driver's breath. Use of these sensors is not believed to constitute a search under the fourth amendment and can be used by officers to establish probable cause that a driver has been drinking.
In one recent study, police detected 55 percent of drivers above the legal BAC limit when not using passive sensors, compared with 71 percent when using sensors (Ferguson et al. 1995). In addition, Jones and Lund (1986) found that when sensors are used, sober drivers are less likely to be erroneously suspected of alcohol use, and a lower percentage are asked to take field sobriety tests.
Perhaps the most extensive State wide sobriety checkpoint program in the United States was implemented in Tennessee. From April 1994 through March 1995, more than 150,000 drivers were stopped at 900 checkpoints. The program was highly publicized on tele vision. A quasiexperimental study revealed a 17percent reduction in alcoholrelated fatal crashes in Ten nessee relative to five contiguous States during the same time period (Lacey et al. 1996).
Preliminary breath testers have been available to police for more than 20 years. They are generally used after the police officer has conducted a field sobriety test and are useful in establishing probable cause for intox ication. States with laws permitting the use of preliminary breath tests at the roadside have been found to reduce nighttime fatal crashes significantly, even after the results were controlled analytically for a dozen potential con founding variables such as unemploy ment, income, alcohol taxes, miles driven, and drinking.

Comprehensive Community Inter ventions.
Enforcement is most likely to be effective in deterring alcohol impaired driving if it is publicized, and it is most likely to be actively pursued by the police if they feel there is a strong demand for such action.
Citing its longterm success with other public health problems, the In stitute of Medicine of the National Academy of Sciences has recom mended comprehensive multistrategy community interventions to reduce alcoholrelated health problems. For example, comprehensive community programs have achieved some success in reducing cardiovascular mortality and risks such as fat intake, blood pressure, smoking, and cholesterol level. Some recent community inter ventions have achieved minimal re ductions in cardiovascular risks and prevalence of smoking; however, one study found significant declines in unintentional childhood injury.
The Saving Lives Program was im plemented in March 1988 (Hingson et al. 1996b). In each of six Massachu setts cities (combined population of 318,000), a fulltime coordinator from the mayor's or city manager's office organized a task force of concerned private citizens and organizations and officials representing various city de partments (e.g., school, health, police, and recreation). Each community re ceived approximately $1 per inhabitant annually in program funds. Active taskforce membership ranged from 20 to more than 100 persons, and an average of 50 organizations partici pated in each city. The communities not only attempted to reduce alcohol impaired driving but also targeted other risky driving behaviors that alcoholimpaired drivers are more likely to engage in, such as speeding, red light violations, failure to yield to pedestrians in crosswalks, and failure to wear seatbelts.
Fatal crashes in program cities de clined from 178 in the 5 years before the program to 120 during the 5 pro gram years, a 25percent decrease relative to the rest of Massachusetts. Likewise, fatal crashes involving al cohol declined by 42 percent relative to the rest of the State, from 69 in the 5 years preceding the program to 36 during the 5 years of the program. The number of fatally injured drivers with positive BAC's showed a decline of 47 percent in program cities, from 49 to 24. Visible injuries per 100 crashes declined by 5 percent, from 21.1 to 16.6. The proportion of vehicles ob served speeding and the proportion of teenagers who reported driving after drinking were cut in half. The results clearly indicate that interventions or ganized by multiple city departments and private citizens can reduce driving after drinking, related driving risks, and traffic deaths and injuries. A major question is whether these changes can be sustained without support from the initial grant sources.
In the Community Trials Program (Holder et al. in press), three experi mental communities-one each in northern and southern California and one in South Carolina-were paired with comparison communities. The program incorporated community mobilization, media advocacy, train ing of alcoholic beverage servers, de velopment of written serving policies by bars and restaurants, local zoning to reduce alcoholoutlet density, local enforcement of underage alcohol sales, alcoholoutlet clerk training in asking for age identification, police officer training, additional officer enforcement hours, use of passive alcohol sensors, and monthly sobriety checkpoints.
In program communities, relative to comparison communities, changes in cluded statistically significant program related increases in media coverage of alcohol issues in local newspapers and on local television, a significant reduction in alcohol sales purchases to minors (i.e., sales were cut in half), and increased adoption of responsible server policies. Across all three program communities, a significant 10percent postprogram reduction occurred in the numbers of SVN crashes per 100,000 population, with the greatest effects in the two California communities.
The results from these two studies reinforce findings from an earlier com munity study in which bartenders and counter clerks were trained to demon strate the use of calculators to identify customer BAC levels based on cus tomer weight and the number of drinks consumed. Television spots reinforced the messages. Roadside surveys con ducted in both the intervention and the comparison communities before the program was implemented and 6 months after it was implemented revealed no differences between communities be fore the program was initiated. At the 6month survey, 5.8 percent of night time drivers in the program communi ties had BAC's of 0.05 percent or higher, compared with 11.1 percent in the comparison communities. This study demonstrates the potential for community interventions to change social norms about unacceptable drinking behavior before driving.

POTENTIAL AREAS OF RESEARCH
Despite the progress made in reducing alcoholrelated crashes since the early 1980's, the increase in such crashes in 1995 reminds us that important research questions persist.

Enforcement Decline: Cause and Effects
Arrests for drunk driving have declined 26 percent since 1983. The reasons for those declines are not clear. Whether they reflect changes in attitudes among police command staff and patrol offi cers searching for DUI offenders or in the exercise of discretion in arresting offenders warrants exploration. The im pact of reduced arrest rates on drivers' perceptions of the likelihood that alcoholimpaired drivers will be ar rested also deserves scrutiny.

Enforcement of Related Traffic Laws
People who drive after drinking alco hol are more likely than other drivers to speed, run red lights, fail to yield to pedestrians, and fail to wear seatbelts. All of these behaviors heighten the risk of crashing or of being injured in a crash. The community program re ported by Hingson and colleagues (1996b) in Massachusetts targeted not only alcoholimpaired driving but also these related driving behaviors. Whether this strategy can succeed in other States warrants exploration. Massa chusetts did not have a seatbelt law during that study period. Combining DUI enforcement with seatbelt check points should be explored, particularly in States with primary seatbelt law en forcement that permit police to stop a vehicle because occupants are unbelted. Similarly, combining DUI and speed enforcement warrants study, because a high proportion of fatal crashes in volving alcohol also involve exces sive speed.

Pedestrians and Alcohol.
In 1995, 5,585 pedestrians died in alcohol related crashes. Twenty percent of the drivers and 37 percent of the pedestri ans had been drinking. Most attention on alcoholinvolved traffic crashes has focused on drivers. Jones et al. (1992) found that adopting the MLDA of 21 reduced the number of both teenage driver and pedestrian deaths. Whether policy initiatives, such as lower legal BAC limits, alcohol taxes, zoning, or altering hours of sale, can influence pedestrian deaths deserves study. Ross (1992) has indicated that most legal and community approaches to date have emphasized legal deterrence of alcoholimpaired driving. Less polit ical discussion has focused on social causes of impaired driving. Ross insists that impaired driving can also be re duced by policies that decrease the overall use of cars as well as of alcohol.

General Transportation Changes.
In addition, other strategies should be explored, including taxes and regula tions on vehicles, gasoline, and alcohol sales; improved public transportation; and restrictions on driver age. Ross has also urged an examination of ef forts to attenuate links between impair ment, error, and crashes and between crashes, injuries, and deaths. Exam ples include improved highway and vehicle engineering and improved emergency medical services.

CONCLUSION
Since the early 1980's, legislative in itiatives, such as the MLDA of 21, ad ministrative license revocation, and lower legal BAC limits for youth and adults, have been independently associ ated with significant declines in alcohol related traffic deaths. Active education and enforcement programs can enhance the beneficial effects of these laws. Furthermore, comprehensive commu nity interventions that integrate the efforts of several city Government departments with those of concerned private citizens and organizations can substantially reduce alcoholrelated traffic deaths, particularly if the pro grams also devote attention to other risky traffic behaviors disproportion ately found among drinking drivers (e.g., speeding, running red lights, and failure to wear seatbelts). Nonetheless, although increases in the implementa tion of MLDA laws, traffic laws, and programs have helped cut alcohol related traffic deaths by 31 percent nationwide, the bulk of the problem persists: Alcoholrelated traffic deaths increased 4 percent in 1995, the first increase in a decade. Research is need ed to explore ways to increase police enforcement of existing drunkdriving laws, to foster the passage of legisla tion known to reduce traffic injury and death, and to explore new ways to re duce alcoholrelated traffic deaths, not only among drivers and passengers, but also among pedestrians. Furthermore, new ideas and new approaches will be needed if we are to make dramatic additional advances addressing this major public health problem. ■